TITLE:
Interannual Variability of Mediterranean Sea SST and Algerian Winter Rainfall
AUTHORS:
Mouna Mohamadi, Mdelele Juma Said, Charafa El Rhadiouini, Iqra Zainab, Anas Farooq
KEYWORDS:
Mediterranean SST, DJF Rainfall, Algeria, EOF Analysis, Atmospheric Circulation, Climate Variability, ENSO
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.13 No.11,
November
26,
2025
ABSTRACT: This study examines how Algeria’s winter (December-February, DJF) rainfall is affected by the trends and variability of the Mediterranean Sea Surface Temperature (SST) between 1993 and 2023. Empirical Orthogonal Function (EOF) analysis and composite diagnostics were used to identify dominant SST modes and their atmospheric linkages using high-resolution datasets (ERSST, CHIRPS, and NCEP/NCAR reanalysis). The second Mediterranean SST mode (EOF2), which is the main cause of rainfall variability in Algeria, accounts for 25.3% of the variance in SST and is distinguished by a zonal dipole (eastern cooling vs. western warming). The associated atmospheric patterns show that whereas cool phases reduce precipitation through anticyclonic conditions and subsidence, warm SST phases increase rainfall through cyclonic circulation, increased vertical motion, and moisture flux convergence. The study concludes that the interannual and annual variation of Mediterranean SST is one of the key regulators of the winter hydroclimate in Algeria, and it has important implications, for the variability of water resources in the region. The importance of interannual SST variability over long-term trends in regulating Algeria’s winter hydroclimate is also highlighted by these findings, which are worth studying in the future.